Mike Tyson is seriously messed up — just ask him. Or watch his TV show. Or read his book.

The former heavyweight champion renowned for his devastating punching power is now known for the knee-buckling effect of his constant sharing: tortured revelations, in a variety of settings, about his violent past, suicidal tendencies and rampant murder fantasies.

In his new autobiography “Undisputed Truth,” Tyson goes through 15 rounds of his rough Brooklyn upbringing, athletic exploits, drug and alcohol addictions and jail time on a rape conviction. And then there’s this wicked uppercut:

“Sometimes I just fantasize about blowing somebody’s brains out so I can go to prison for the rest of my life,” he writes. “Working on this book makes me think that my whole life has been a joke.”

That’s about killing someone else. Typically, of late, Tyson’s painful confessions have concerned his thoughts about suicide, about his own death.

On a conference call in mid-August preceding his latest promotional tour, Tyson told reporters, somewhat unprompted, “I was planning on killing myself” following his daughter’s accidental strangling death in 2009.

In late August, on NBC’s “Today,” he said: “When I start drinking and I relapse, I think of dying. Normally I’m in a real dark mood, I think of dying, and I don’t know if I want to be around no more.”

Tyson is also the subject of a behind-the-scenes documentary series on Fox Sports 1 titled “Being: Mike Tyson” in which he explores the roots of his damaged psychology and discusses his personal demons.